Nanometer-scale particle recycled slurry paper

ABSTRACT

The present invention discloses a nanometer-scale particle recycled slurry paper. The shares in weight of its ingredients are: papermaking wastewater slurry 20-80, pulp 20-80, nanometer-scale calcium carbonate 2-20, and chemical auxiliary agent performing the function of coacervation 1-5. The production technology process of the present invention is: slurry→pressing and squeezing the slurry→washing and filtering→putting into a pool→adding nanometer-scale calcium carbonate→mixing the paper pulp with the chemical auxiliary agent performing coacervation function→stirring and mixing→transferring onto a mesh→pressing and squeezing→drying→forming into paper→winding into reels.

FIELD OF THE INVENTION

[0001] The present invention relates to a recycled slurry paper, and more particularly to a formula of the recycled slurry paper and its papermaking process by means of nanometer-technology.

BACKGROUND OF THE INVENTION

[0002] Slurry is usually discarded as trash after wastewater treatment in a paper mill, even if the slurry still contains a sufficient amount of fibre, because the slurry needs store space and is likely to lead to pollution of the environment. Although a few paper mills utilize the slurry to produce paperboards, they can only be used for interlayer paperboards of low-level leather products, which are in low price and unmarketable. Consequently, nowadays, the development and research of the slurry paperboard have become an important task of paper mills in order to prevent pollution and to get economic benefits.

[0003] Currently, high and advanced nanometer-technology is being applied in many industries such as plastics, synthetic fibres, magnetic materials, coating materials, printing and dyeing, catalysts, ceramics and accumulators. Compared with these of conventional materials, nanometer-scale materials have more excellent physical, chemical, mechanical and biological properties and other specific properties that conventional materials do not have. Moreover, when nanometer-scale materials are utilized in conventional materials, it is possible to considerably improve the property and grade of products made by conventional materials, and to make these conventional products upgraded. Applying the nanometer-scale material in papermaking is still at the experimental stage. In the meantime, utilizing nanometer-technology for manufacturing recycled slurry paper is a research target for development of papermaking mills at present.

SUMMARY OF THE INVENTION

[0004] An object of the present invention is to provide a nanometer-scale particle recycled slurry paper making use of papermaking wastewater slurry and a papermaking process by means of an applied nanometer-technology.

[0005] In order to achieve the above-mentioned object, the technical scheme adopted is: papermaking wastewater is processed via vapour floatation physical treatment, the remaining slurry is used as base material of nanometer-scale particle recycled slurry paper, nanometer-scale calcium carbonate and a chemical auxiliary agent comprising macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer are added into the slurry in order to perform the function of coacervation. Since nanometer-scale calcium carbonate has surface adsorption function, the chemical auxiliary agent comprising macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer performs the function of adsorption and polymerization, they enwrap fine fibres and attach fine fibres onto the paper so as to greatly improve the quality of paper.

[0006] The share in weight of the ingredients of the nanometer-scale particle recycled slurry paper of the present invention is: the papermaking wastewater slurry 20-80, pulp 20-80, nanometer-scale calcium carbonate 2-20, and chemical auxiliary agent performing the function of coacervation 1-5. In the above ingredients, the chemical auxiliary agent performing the function of coacervation comprises macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer. The percentage in weight of the ingredients of the chemical auxiliary agent performing coacervation function is that: macromolecular emulsifying agent with negative charge is 30-40%, polymers mainly consisting of acrylic amide monomer is 35-45%, and the rest is additive.

[0007] The production process of the present invention is: slurry→pressing and squeezing the slurry→washing and filtering→putting into a pool→adding nanometer-scale calcium carbonate→mixing the paper pulp with the chemical auxiliary agent performing coacervation function→stirring and mixing→transferring onto a mesh→pressing and squeezing→drying→forming into paper→winding into reels.

[0008] The present invention provides the following advantages and benefits:

[0009] (a) new and advanced nanometer-technology is utilized during the manufacturing process of nanometer-scale particle recycled slurry paper. Since the nanometer-scale calcium carbonate and the chemical auxiliary agent comprising macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer have the function of adhering and cohering fibres together, the quality and performance of the paper are improved, degree of smoothness, tensile strength, durability and folding resistance are also improved apparently,

[0010] (b) makes full use of the discarded papermaking slurry to reproduce paper for achieving the objects of recycling waste material and reducing energy consumption,

[0011] (c) purifies the environment, reducing pollution and protecting ecological environment,

[0012] (d) replaces the conventional crude paper for saving cost, the economic benefit is also considerable,

[0013] (e) reaches the normal technical standard when used in making corrugated paperboard. The present invention is suitable to be used in the treatment of wastewater slurry in paper mills.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0014] The following are further detailed description of the present invention with reference to embodiments.

[0015] The slurry is a waste material after papermaking, but it contains a certain amount of the fibres. However, fibres in the slurry are too fine to be put onto the mesh and the loss of the fibres is very considerable, so it is necessary to add a certain amount of the pulp and the additive into the slurry in order to increase the consistency of the fibres.

[0016] Embodiment 1

[0017] Take papermaking slurry 70 kg, pulp 20 kg, nanometer-scale calcium carbonate 5 kg and chemical auxiliary agent 5kg among which the macromolecular emulsifying agent with negative charge and the polymers mainly consisting of acrylic amide monomer respectively accounts for 32% and 36% and the rest is additive. Firstly, having been pressed and squeezed, washed by clean water and filtered, the papermaking slurry is then put into a pool. Pulp, nanometer-scale calcium carbonate, chemical auxiliary agent comprising macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer are added in the pool, stirring and mixing equally. The slurry, after being equally mixed, is transferred onto the mesh on the production line by a pump, is then squeezed and dried, the finished nanometer-scale particle recycled slurry paper is obtained.

[0018] Embodiment 2

[0019] Take papermaking slurry 64 kg, paper pulp 30 kg, nanometer-scale calcium carbonate 3 kg and chemical auxiliary agent 3 kg among which the macromolecular emulsifying agent with negative charge and the polymers mainly consisting of acrylic amide monomer respectively accounts for 36% and 40% and the rest is additive. Firstly, having been pressed and squeezed, washed by clean water and filtered, the papermaking slurry is then put into a pool. Pulp, nanometer-scale calcium carbonate, chemical auxiliary agent comprising macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer are added in the pool, stirring and mixing equally. The slurry, after being equally mixed, is transferred onto the mesh on the production line by a pump, is then squeezed and dried, the finished nanometer-scale particle recycled slurry paper is obtained.

[0020] Embodiment 3

[0021] Take papermaking slurry 55 kg, pulp 35 kg, nanometer-scale calcium carbonate 8 kg and chemical auxiliary agent 2 kg among which the macromolecular emulsifying agent with negative charge and the polymers mainly consisting of acrylic amide monomer respectively accounts for 39% and 43% and the rest is additive. Firstly, having been pressed and squeezed, washed by clean water and filtered, the papermaking slurry is then put into a pool. Pulp, nanometer-scale calcium carbonate, chemical auxiliary agent comprising macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer are added in the pool, stirring and mixing equally. The slurry, after being equally mixed, is transferred onto the mesh on the production line by a pump, is then squeezed and dried, the finished nanometer-scale particle recycled slurry paper is obtained. 

We claim:
 1. A nanometer-scale particle recycled slurry paper, characterized in that the shares in weight of its ingredients are: papermaking wastewater slurry 20-80, pulp 20-80, nanometer-scale calcium carbonate 2-20, and chemical auxiliary agent performing the function of coacervation 1-5.
 2. A nanometer-scale particle recycled slurry paper as claimed in claim 1, characterized in that the chemical auxiliary agent performing the function of coacervation comprises macromolecular emulsifying agent with negative charge and polymers mainly consisting of acrylic amide monomer.
 3. A nanometer-scale particle recycled slurry paper as claimed in claim 1 or 2, characterized in that the percentage in weight of the ingredients of the chemical auxiliary agent performing coacervation function is that: macromolecular emulsifying agent with negative charge is 30-40%; polymers mainly consisting of acrylic amide monomer is 35-45%; the rest is additive.
 4. A nanometer-scale particle recycled slurry paper, characterized in that its production process is: slurry→pressing and squeezing the slurry→washing→putting into a pool→adding nanometer-scale calcium carbonate→mixing the paper pulp with the chemical auxiliary agent performing coacervation function→stirring and mixing→transferring onto a mesh→pressing and squeezing→drying→forming into paper→winding into reels. 